The present invention relates generally to availability versus the number of active redundant components in an information technology system or subsystem.
One way of expressing the requirement for high availability in an information technology system or subsystem is through a recovery time objective (RTO), which specifies the amount of time it takes to recover from a failure in the system. The prior art makes use of power consuming, redundant components to improve the recovery time objective of systems and subsystems. Thus the cost of providing high availability in a system or subsystem involves an increase in power consumption.
As an example, one method of providing high availability is illustrated by U.S. Pat. No. 7,043,650 (patent application Ser. No. 10/000,703, filed on Oct. 31, 2001), which discloses a system and method for intelligent control of power consumption of distributed services during periods when power consumption must be reduced. Distributed services are provided by computer systems and the system and methods pertaining to this invention selectively shutdown services.